Breaking the Symmetry of a Metal–Insulator–Metal-Based Resonator for Sensing Applications

Abstract

This article designed a novel multi-mode plasmonic sensor based on a metal–insulator–metal waveguide side-coupled to a circular-shaped resonator containing an air path in the resonator. The electromagnet field distributions and transmittance spectra are investigated using finite element method-based simulations. Simulation results show that an air path in the resonator's core would impact the transmittance spectrum of SPPs. Besides, the air path is crucial in offering efficient coupling and generating multiple plasmon modes in the sensor system. The proposed structure has the advantage of multi-channel, and its sensitivity, figure of merit, and dipping strength can reach 2800 nm/RIU, 333.3 1/RIU, and 86.97%, respectively. The achieved plasmonic sensor can also apply for lab-on-chip in biochemical analysis for detecting the existence or nonappearance of diabetes through the human glucose concentration in urine.

Multi-resonance plasmonic refractive index sensor based on maze-shaped resonators for biological applications

“…RMs with narrower FWHMs can lead to more accurate detection in RI sensing [40]. The difference between the maximum and minimum transmittance of RM is defined as the dip strength (∆T = (T max − T min ) × 100%) [41,42]. A higher dipping strength improves sensing accuracy, as it is easier to detect a sensing signal with a strong resonance [41,42].…”

“…The difference between the maximum and minimum transmittance of RM is defined as the dip strength (∆T = (T max − T min ) × 100%) [41,42]. A higher dipping strength improves sensing accuracy, as it is easier to detect a sensing signal with a strong resonance [41,42]. The sensing resolution (SR) is an important indicator that determines slightest detectable variation in RI by the sensor.…”

Dynamic Regulation of Multiple Fano Resonances Based on Liquid Crystal

“…Fano resonance with the characteristics of the sharp asymmetric line shape and strong-field enhancement, has attract researches' attentions. Owing to advantages of confining light and long propagation length, Fano resonance based on Metal-Insulator-Metal (MIM) structure have been intensive studied, and the applications are very broad, such as hemoglobin detection [11], cancer biomarker [12], sensing [13]- [15], filter [16] and so on. Moreover, as is well known, when light inject into MIM waveguide, the MIM structure can support the SPs which can be excited in the surface of metal and insulator.…”

Ultra-wide bandstop infrared MIM filter using aperture coupled square cavities

“…Functional devices based on MIM plasmonic waveguide such as directional couplers [14,15], switches [16,17], splitters [18], sensors [19,20], optical gates [21,22] and antenna [23] have been designed. Tunable bandpass and bandstop MIM plasmonic filters can be employed in multiplexers and de-multiplexers [24][25][26], light speed controlling [27] and optical switching [28].…”